The present invention relates to fiber-optic communication systems, and more particularly, to optical communications systems having communications links for communicating with subsystem components.
Optical communications systems are typically made up of spans of transmission fiber that are interconnected at system nodes. The system nodes may contain optical subsystems such as optical amplifiers and add/drop modules. Optical amplifiers are used to amplify optical signals on the transmission fiber.
In a wavelength division multiplexing system, multiple communications channels are provided using multiple wavelengths of light. Add/drop modules may be used to extract a selected group of wavelengths from the transmission fiber for use by a local network. The add/drop modules may also be used to reintroduce the dropped wavelengths to support communications that originate in the local network.
An optical communications network may have network control and management software and an overall optical network operating system that allows the status of certain optical subsystem components to be monitored or controlled. One of the multiple wavelengths of light in a wavelength division multiplexing system may be used to support a telemetry channel that is used for this purpose. Optical filters may be used at the system nodes to separate the telemetry channel from the normal communications channels supported by the fiber.
It may be difficult to add new subsystems to an optical communications network unless the new subsystems are compatible with the existing network control and management system software and telemetry channel arrangement. If a new network component does not interact properly with the existing system infrastructure, it may not be possible to monitor or control the new component after it has been installed or the new component may interfere with the operation of the network. Moreover, some network maintainers may wish to add new subsystems to the network without modifying the existing network software to make it compatible with the new subsystems. This is because the existing network software may have been developed by a third-party or because it is too complicated or too risky to make such modifications.
It is an object of the present invention to provide ways in which to facilitate the addition of subsystems to optical communications networks.
It is another object of the invention to provide optical communications systems arrangements in which communications links other than standard optical telemetry channels may be used to monitor or control optical subsystem components.
These and other objects of the invention are accomplished in accordance with the present invention by providing arrangements for optical communications networks that allow network maintainers to monitor or control subsystems using communications links other than standard optical telemetry links. The communications links may be wireless links or may be based on any other suitable communications links such as links using Ethernet cables or telephone lines. Wireless communications links that may be used include wireless links based on satellite communications, cellular telephone communications, paging communications, or any other suitable wireless communications arrangement.
Subsystems may be provided for the network that include communications circuitry for communicating over the communications links. The network maintainer may use network control and management software implemented on computer equipment to communicate with the subsystems over the communications links. Because the communications links may function independently from the optical telemetry channels in the network, new subsystems may be added to the network without disturbing the existing network management software or telemetry arrangement.
Further features of the invention and its nature and various advantages will be more apparent from the accompanying drawings and the following detailed description of the preferred embodiments.